Two component, molded plastic dispenser operating on push-pull principle

Abstract

A two piece, molded plastic dispenser, that functions with a push-pull motion, comprising an outer shell and an inner shell. The outer shell comprises a top wall with an aperture defined at its center, and a skirt of generally cylindrical shape. A plug seal extends below the top wall, and annular groove and bead are formed in the vicinity of the upper end of the inner surface of the skirt and the underside of the top wall. The inner shell comprises a top wall, a tapered spud extending upwardly from the top wall, an annular barrier encircling the spud, and a depending skirt. Detents and arcuate wall segments extend, in interspersed fashion, about the perimeter of the upper shell, and cooperate with the bead on the outer shell. Vertical ribs on the inner surface of the outer shell cooperate with serrations on the exterior surface of the inner shell to guide the relative movement of the outer shell, in a vertical direction, while preventing relative rotation between the shells. The contents of the container are discharged through apertures in the inner shell proximate to the spud to flow through the aperture in the outer shell. The plug seal and annular barrier, and the spud and aperture, are fully engaged, when the dispenser is closed, to provide leak-proof operation. The arcuate walls segments extend vertically above the detents to protect same, and the underside of the annular bead abuts a shoulder on each wall segment when the dispenser is closed.

We claim: 
     
       1. A molded plastic dispenser adapted to be secured to a container for discharging the contents thereof, said dispenser comprising: a) an outer shell comprising a top wall, a discharge aperture in said top wall, and a depending cylindrical skirt,   b) an inner shell configured to fit snugly within said outer shell,   c) said inner shell comprising a top wall and a depending skirt,   d) a spud extending upwardly from said top wall of said inner shell,   e) flow passages formed through said top wall of said inner shell adjacent said spud,   f) cooperating mechanical members defined between the interior surface of said skirt of said outer shell and the exterior surface of said skirt of said inner shell to prevent relative rotation therebetween,   g) relative movement between said shells alternately seating said spud within said aperture to prevent discharge, and withdrawing said spud from said aperture to allow flow of product through said flow passages, along said spud, and through said discharge opening,   h) stops distributed about the interior of the depending skirt of said outer shell to limit the relative movement of said inner shell and prevent disassembly of said shells,   i) an annular, inwardly extending bead is located on the inner surface of said outer shell,   j) and a plurality of detents extend upwardly from said top wall of said inner shell, said detents snapping into engagement with said bead on said outer shell to retain said shells in closed, non-dispensing position.   
     
     
       2. A dispenser as defined in claim 1 wherein said plurality of detents are three in number, and said detents are spaced at 120° intervals. 
     
     
       3. A dispenser as defined in claim 1 wherein arcuate segmental walls are interspersed with said detents, said segmental walls extending vertically a short distance above said detents, said segmental walls being rigid and non-yielding to protect said detents from vertically directed impact and loading forces. 
     
     
       4. A dispenser as defined in claim 3 wherein three identical arcuate segmental walls extend above the upper wall of said inner shell. 
     
     
       5. A dispenser as defined in claim 3 wherein a shoulder is defined on the outer surface of each segmental wall, and said annular bead on said outer shell abuts against said shoulder when the dispenser is in the closed position. 
     
     
       6. A dispenser as defined in claim 1 wherein said detents are cantilevered fingers. 
     
     
       7. A dispenser as defined in claim 6 wherein each of said cantilevered fingers terminates in an enlarged head, at its upper end, which snaps into locking engagement with said bead. 
     
     
       8. A dispenser as defined in claim 1 wherein said spud is hollow, and tapers from a wide base to a narrower top. 
     
     
       9. A dispenser as defined in claim 8 wherein an annular relief groove is formed in the underside of the top wall of said outer skirt in the vicinity of said aperture, said groove imparting flexibility to the area surrounding said aperture so said spud can easily by seated within, and withdrawn from, said aperture. 
     
     
       10. A dispenser as defined in claim 1 wherein a plug seal depends below the top wall of said outer shell, and an annular barrier encircles said spud, said plug seal contacting said annular barrier when said shells are joined together. 
     
     
       11. A dispenser as defined in claim 10 wherein said plug seal has a bulbous shape for increased sealing action. 
     
     
       12. A dispenser as defined in claim 1 wherein said stops are formed as a discontinuous bead on the inner surface of said outer shell. 
     
     
       13. A dispenser as defined in claim 1 wherein an annular groove is defined in the inner surface of said outer shell below the intersection of said top wall and said depending skirt, and adjacent to said annular bead. 
     
     
       14. A molded plastic dispenser adopted to be secured to a container for discharging the contents thereof, said dispenser comprising: a) an outer shell comprising a top wall and a depending cylindrical skirt,   b) a discharge aperture located in said top wall of said outer skirt,   c) an inner shell configured to fit snugly within said outer shell,   d) said inner shell comprising a top wall and a depending skirt,   e) a spud extending upwardly from said top wall of said inner shell,   f) flow passages formed through said top wall of said inner shell adjacent said spud,   g) cooperating mechanical members defined between said inner shell and said outer shell to permit movement therebetween,   h) stops distributed about the interior of the depending skirt of said outer shell to limit the movement of said inner shell and prevent disassembly of said shells, the invention being characterized by: i) an annular barrier extending upwardly from the top wall of said inner shell,   j) said annular barrier circumscribing said spud and said flow passages,   k) a plug seal depending below the top wall of said outer skirt,   l) said plug seal circumscribing said discharge aperture, said plug seal contacting said annular barrier at all times to prevent leakage past the seal created by the central aperture being forced over said spud.     
     
     
       15. A dispenser as claimed in claim 14 wherein said spud tapers inwardly as it extends above said top wall of said inner shell, and said plug seal is bulbous in shape to maximize the area of contact with said annular barrier.